“The tower is too narrow,” the computer began. “You have too much airspeed to land on it without reverse thrust-” but it was too late. The Compass Tower came at them, a slanting wall rising well overhead, visible now through the clear spots to either side and above. Wolruf held their angle of approach until it seemed they were about to smash headlong into it, then at the last moment pulled back hard on the control handle and brought them up almost parallel to the slanting wall.

The pyramid-shaped tower rose up out of the jungle at about a sixty-degree angle. They hit at about fifty, give or take a few degrees. The violent lurch of impact threw everyone against their restraints, and even Mandelbrot took a step to avoid losing his footing; then with a screech of metal sliding on metal they skidded up and over the top edge of the tower.

Cabin gravity had died completely in the collision. They felt a sickening moment of weightlessness, then another lurch as they smashed sideways onto the flat top and continued to skid along its surface. All four of the control room’s occupants watched with morbid fascination as the far edge drew nearer.

“Frost, I should’ve gone comer to comer,” Wolruf growled, and for a moment it seemed as if that would be their epitaph, but as they slid across it the surface of the tower grew rougher ahead of them, and the ship ground to a halt with four or five meters to spare.

Derec found that he had nearly crushed Ariel’s hand in his own. He would have if she hadn’t been gripping him almost as fiercely herself. Breathing hard, neither of them willing to test their voices yet, they loosened their hold on each other and flexed their bruised fingers.

Wolruf let out a sigh, pulled her seat restraints loose, and braced herself to stand on the tilting floor. “Well,” she said, “welcome ‘ome.”

Some hours later, Wolruf stood at the base of the tower and peered out into the dense jungle surrounding it. She had begged off from the congratulatory dinner Ariel had suggested, claiming stomach cramps from the anxiety and excusing herself to go take a run to stretch her muscles. She fully intended to go for a run, if only to guarantee her solitude, but in truth the reason she wished to be alone was not stomach cramps but shame. Despite her companions’ congratulations-even Avery had commended her for her flying skill, while making a not-so-subtle jab at Derec for creating the birds that had made that skill necessary in the first place-despite their heartfelt thanks, Wolruf knew that it was she, not Derec, who was ultimately responsible for the accident in the first place.

Stupid, stupid, stupid, to circle low above a forest and not watch out for birds. Especially an unfamiliar forest, full of unfamiliar and unpredictable species. If she’d pulled a stunt like that at home, she’d have been kicked out of the training academy so fast her tail wouldn’t even have been caught in the slammed door.

Yes, she’d shown some quick thinking afterward, had pulled their collective fat out of the fire, but all the praise she got for that bit of fancy flying simply galled her all the more. Her initial mistake had nearly killed them all.

“So you learn from your mistakes,” she growled in her own language, quoting one of her old instructor’s favorite phrases, but hearing the guttural gnashing and snarling of her native tongue brought a sudden pang of homesickness, and she cocked back her head and let fly a long, plaintive howl.

An echo bounced back at her from the trees. Then, faintly, coming from far deeper in the jungle, she heard an answering cry.

A cold shiver ran down her back at the sound of it. It wasn’t exactly an answer-not in words, at any rate-but the meaning was just as clear as her own howl had been. You are not alone.

And just who might be making so bold an assertion on this planet so recently filled only with robots? Wolruf had no idea. The odds of it being a member of her own species were no odds at all; she was the only one of her kind in human space, and she knew it. But whatever mouth had voiced that cry belonged to a creature at least similar to herself, and it had given her an open invitation for companionship.

At the moment she wasn’t feeling picky. She took a deep breath, tilted her head back and howled again, forgoing words for deeper meaning: 1 am coming. Not waiting for an answer, she struck off into the trees.

Ariel heard the howling from her room in the apartment they had chosen practically at random from among thousands in the underground city. The windows were viewscreens, currently set to show the scene from partway up the Compass Tower, and they evidently transmitted sound as well. Ariel had been brushing out her hair; she stopped with the brush still tangled in a stubborn knot of dark curls, stepped to the window, and listened. Another howl echoed through the forest, and another. One was recognizably Wolruf, but not both. A bird added a shriek of alarm-or perhaps derision-to the exchange.

Some primitive instinct triggered her hormonal reflexes, dumping adrenaline into her bloodstream, readying her to fight or flee should either need arise. She felt her pulse rate quicken, felt the flush of sudden heat in her skin.

The howls came again.

She swallowed the taste of fear. She was ten levels below ground! “So strange, to hear live animal sounds here,” she whispered.

Derec lay on the bed, one arm draped over his eyes and the other sprawled out at his side. He shifted the one enough to peer under it at Ariel and said, “It is. I think I like it, though.”

“Me too.” Another howl made her shiver, and she added, “As long as I’m inside, anyway.”

“Don’t get too attached to it. Avery’ll probably have the whole thing covered in city again inside of a week.”

Ariel tugged at her brush again, got it through the tangle, and took another swipe at it. “Do you really think he will?”

“I imagine. He sounds pretty intent on it.”

“Couldn’t you stop him? Your order has precedence. If you tell the robots you want it to stay the way it is, they’ll obey you, won’t they?”

“Maybe. I don’t know if it’s worth it.”

“Hmm,” she said. Maybe it wasn’t. Easy come, easy go, and all that. Besides, Avery had just been beginning to act like a human being before he discovered Derec’s ecosystem project; maybe it would be worth it to let him put the city back the way he’d originally planned it if it would keep him easy to get along with.

“Where’d he go, anyway?” she asked.

Derec let his arm flop down over his eyes again. “Computer center, where else?”

“Of course.” Ariel turned away from the window and walked back over to stand in front of the mirror. She continued to brush her hair, but she watched Derec’s reflection, not her own. She could have stared at him directly, since he had his eyes closed, but somehow she liked using the mirror, as though she might see something in it that she wouldn’t otherwise.

What she saw pleased her well enough no matter which way she viewed it. Derec was trim, well-muscled, attractive by nearly anyone’s standards. Certainly he was attractive by Ariel’s. She had fallen in love with him twice now, without the complication of falling out of love in between. Amnesia had its good points.

And he had fallen in love with her twice, too. At least she thought so. Once, definitely, and that was this time, so what did it matter if the first was merely infatuation, as she suspected it had been? He loved her now, didn’t he?

As if he could read her mind, she saw him raise his arm up again and peek out at her from under it, and the openly appreciative smile that spread across his face told her all she needed to know. He raised up off the bed in one smooth motion, came over to nuzzle his face in the hollow between her neck and shoulders, and whispered, “So why don’t we take a blanket and go for a walk in the forest while it’s still there?”